Method of wood protection



UNITED STATES PAUL nausea, 0] WASHINGTON, DISTRICT OI OOLUIBIA- METHODOF WOOD PROTECTION.

He Drawing.

To all whom'itma concern:

Be it known til lat I, PAUL BAR'I'SOH, a citizen of the United States,residing at Washington, in the District of Columbia have invented a newand useful Method oi Wood Protection, of which the following is a secification.

his invention relates to a method of treating wood whereby it isprotected against shipworms, borers, dry rot and fungus decay.

T for protecting wood subject to the action of water against shipworms,borers, dry rot and fungus decay have been ineflicient. Where creosoteis used as a protective medium it will leach out in a varying length oftime, depending upon the temperature of the water, leaving the woodexposed to the ravages of the destructive organisms sooner ,or later.Poisons supplied to the fibers of the wood by existing methods will notpenetrate far enough to insure complete protection and after the thinouter shell of the wood has been removed, the rest can easily bedestroyed by the invading organisms.

One of the objects of the present invention is to com letely poison allthe tissues of the wood, the steps of the process bein such as to causethe poisons to permeate a the cells, fibers, vessels, ducts and ores, aswell as the intercellular spaces in t e wood, thereby rendering the woodimmune against the attack of destructive organisms.

Another object is to seal up all the poisons with which the tissues havebeen impre nated, thereby reventin them from leac ing out when thetreate wood is sub ected to rain or submerged in fresh or saltwater.

Another object is to so treat the wood that ever newl cut surface willexpose a poison w ich will promptly kill borers 1n gesting bits of thewood, with the result that shi worms and other destructive animals wilnot have a chance to burrow into the wood because the microscopic larvalform or adult. will be killed long before it will have buried itselfwithin the tissues of the wood. r

.A further object is to so treat the wood as to completely extract thewater and resin from the cells, fibers, vessels, ducts and pores, aswell as the intercellular spaces in the wood and replace them by thepoisons and the sealing medium.

Specification of Letters Patent.

Application filed October 28, 1920. Serial No. 419,068.

e various methods employed heretofore.

Patented Apr. 12, 1921.

With the foregoing and other objects in view, which will appear asethedescription proceeds the invention consists in first completelyeresinizin the wood with a resin solvent such as xy 01 or turpentine oran other chemical used for such pur oses until complete deresinizationhas ta en place. This step of the method leaves the wood in a com letelyderesinized condition with the cells, hers, vessels, ducts and pores, aswell as the intercellular spaces in the wood, saturated with the resinsolvent. This solvent is then replaced by alcohol, or any other watermiscible solution that can be employed for such purpose. The wood isnext immersed in water in which the above solvent is removed. (Wherenon-resinous woods are treated the deresinizing process may beeliminated and the wood may be subj ected at once to the poisoningprocess which follows. The eresinized wood is next subjecte to saturatedsolutions of arsenic and copper compounds which will, conse uently, filthe cells, fibers, vessels, ducts and pores, as well as theinteroellular spaces in the wood. The wood is next saturated with aprecipitant, such as alcohol, which will recipitate the poisons withinthe tissues 0 the wood. This precipitation step is also a part of thenext feature of our treatment, that is, complete dehydration, which isessential to secure complete penetration of the paraflin. The next stepconsists in replacing the li uid in the wood with a parafiin solvent sueas turpentine. Finally the wood is immersed in garaifin heated to abovethe melting point an which has been oisoned with arsenic and co orsalts. T e turpentine in the wood W1 lbe displaced by the 'parailinwhich in turn, will completely im re ate the woo and seal the poisons, tere y rotecting them from the action of water and preventin leaching,

1; will be apparent, from the foregoin that the wood treated in themanner set fort will contain encapsuled poison in eve cell, fiber,vessel, duct and pore, as well as in the intercellular spaces in the wood,throughout the thickness of the. wood. The poisoned parafiin', whiletoxic itself, will seal umll the poisons with which the tissues have nimpregnated. The arsenic compounds will ison the animal praying upon thewood; in the case of dry rot or ungus, the copper salts will have anequally toxic efl'ect upon those organisms, should they attempt topenetrate the treated wood.

The success of the method is due primarily to the complete extraction ofwater and resin from the cells, fibers vessels, ducts and pores, as wellas from the intercellulaf spaces in the wood, by chemical means andreplacing these by poisons and poisoned paraflin. This can only beaccomplished after complete dehydrat on and deresinization have beenefl'ected, because mixing" araflin and water is a physicalimpossiility,'the least trace of water preventing the ingress ofparaflin. It is believed that no other process of wood preservation hastaken this into account. i

What is claimed iss- 1. The hereindescribed method of protectin woodwhich consists in the complete de ydration of the wood and subsequentsaturation of the wood with ison encapsuled or sealed within the wood y'a' substanceinin chemical dehydration of the wood, and

substitution of poisoned paraflin for the moisture displaced from thecel1's,'fibers,

. ing the wood and precipitatin the within the tissues of the woo dispacin with the araifin. 3

pores, ducts, vessels and intercellular spaces 1n the wood. A

4. The hereindescribed method of protecting wood from organisms, whichconsists in deresinizin the; wood with a resin solvent removing t esolvent, subjecting the wood to a saturated, solution of poison,dehydratolson the dehydrant by a paraflin solvent, an immersing the woodin melted oisoned parafiin, to completely impregnate t e wood 5. Theereindescribed method of protecting wood from destructive or anisms,whichconsists in complete dehy ration of the wood, saturation thereofb aarailin solvent, and displacement of t e so vent in the wood by meltedpoisoned paraflin.

6. The 'hereindescribed method of protecting wood from destructiveorganisms, which consists inderesinizing the wood by means of a solventremoving the solvent and resin, replacing t is with a chemical that willnotonly replace the resin solvent but will,

in turn, "be re' laced by an aqueous solution of arsenic an copiper,then chemically dehydrating the Wed to cause precipitation of thepoisons than replacing the dehydrant g a paraflin solvent and wallreplacing t e parafiin solvent is poisone parafiin;

In testimon that claim the foregoing as my own, I ave hereto aflixed mysignature in the prescnceof two witnesses. I

' PAUL BARTEKJ'H.v

Witnesses! r Hammer D. Lawson, Iva E. Sun-sou.

